Physiology of Hearing Flashcards
what type of waves are sound waves
longitudinal waves
what anatomical features are in the outer ear
pinna
auditory canal
what’s impedance matching in the ear
the transfer of energy from the air in the middle ear -> inner ear fluid
what’s the attenuation reflex & which muscles does it involve
tensor tympani & stapedius muscle contract
- contract in opposite directions
- opposing force
- decrease ability to conduct sound (protects ears from loud noises)
what’s the role of the Eustachian tube in the middle ear
balance atmospheric pressure
- ‘pop’
what’s the overall structure of the inner ear
3 semicircular ducts
which part of the ear is the cochlea located
inner ear
at which side is the cochlear narrower
narrower at the apex than the base
at which side of the cochlear duct is the basilar membrane thinner
thinner at the base than the apex
what are the 2 types of fluid in the cochlea
endolymph
perilymph
where is the endolymph stored & what does it contain
scala media (middle section)
- high potassium
where is the perilymph stored & what does it contain
scala timpani (bottom section) & scala vestibule (top section)
- sodium
how does the basilar membrane allow sound waves to travel
different frequencies if sound waves travel different distances along the basilar membrane
- high frequency -> vibrates stiff base -> dissipates quickly (doesn’t travel far)
- low frequency -> energy doesn’t dissipate fast -> wave travels further
where’s the organ of corti found & where is it related to the basilar membrane
in the scala media
- on top of basilar membrane
what type of cells are in the organ of corti & what’re their function
inner & outer hair cells
- convert mechanical energy to changes in mem. potential
